Non-woven mats have been used in the production of rigid polymeric foam boards for the construction of walls, ceilings or insulation panels on the inside or outside of such structures. The mat may be laid down with the reactants necessary for a polymeric foam between two sheet substrates. While the reactant mixture rises, it penetrates the mat and the board produced gains structural integrity as well as other characteristics from the presence of the mat in its interior.
Foam structures utilizing fibrous mats for reinforcement are described in U.S. Pat. Nos. 3,554,851, 3,860,371, 3,865,661 and 3,867,494. However, upon the application of delamination forces such as heat, humidity or simply physical stress, a foam board with a fibrous mat in its interior may delaminate along the plane of the mat itself, thus defeating the reinforcement benefit of the mat.